it's basic physics that hot air is light and it rises up and the cool air being dense, settles at the base. and it is also efficient practice not to let the two mix in a data center. what i dont get is since the hot air is already rising up, why cant we provide outlets near the ceiling so that the air does not mix? why do we need complicated designs to accomplish this?
Good thinking. Actually, it's quite common to use the space above a dropped ceiling as a return air plenum. Installing actual ductwork is quite a bit more complicated and expensive.
@ Ken, are you saying that it is quite possible to just provide just an opening in the ceiling near the hot aisle and expect efficient cooling to take place? or is it necessary to feed the hot air back to CRAC?
i mean that in data centers, a lot of power is being consumed to ensure proper cooling. In order to reduce power consumption, a common practice is to keep the cold air and the hot air from mixing. for that a lot of spe############ts develop expensive strategies. my question is why we cant just let the hot air that is anyway rising to the ceiling escape from a small outlet instead of all the complicated designs.
@ Ken, are you saying that it is quite possible to just provide just an opening in the ceiling near the hot aisle and expect efficient cooling to take place? or is it necessary to feed the hot air back to CRAC?
Top-fed CRACs are usually equipped with collars to connect them to the ceiling plenum. Return air grilles can be strategically placed above the hot aisles to maximize hot air return. Sometimes the racks are also ducted directly to the ceiling.
hot air outlet
